Mark Schurr uses ground-penetrating radar as other researchers look on during an archaeological expedition at Midewin National Tallgrass Prairie. Researchers will be heading to Midewin once again this summer as part of an ongoing archaeological investigation.

Mark Schurr uses ground-penetrating radar as other researchers look on during an archaeological expedition at Midewin National Tallgrass Prairie. Researchers will be heading to Midewin once again this summer as part of an ongoing archaeological investigation. (University of Notre Dame)

About 400 years ago, a group of people set up camp just south of Joliet, engaging in agriculture and hunting for about 10 summers. Several decades later, the group disappeared.

Now, their trash has become archaeological treasure that could provide clues about what happened to that culture. And they’re inviting local volunteers to help with the project.

A research team from the University of Notre Dame will once again this summer conduct an archaeological dig in western Will County looking for further signs of that ancient Native American culture. They will be digging at what’s now known as the Middle Grant Creek site inside the Midewin National Tallgrass Prairie.

This will be the third year researchers Mark Schurr and Madeleine McLeester will be leading the expedition at the 2-acre site that was discovered to be significant in 2006.

They’ve previously found artifacts there from people of the Oneota culture, which existed from about 1150 until about 1700.

The researchers said markings on pottery fragments indicate the artifacts from the Midewin site date to about 1600.

They said they’ve also discovered deep storage pits containing stone tools and shells originating as far away as Florida.

McLeester said Native Americans had trade routes stretching from Canada down to Florida.

“How those (trade routes) operated is another question,” she said.

At one point, the Oneota inhabited what would become the entire Chicago area, with a territory that went from the southern end of Lake Michigan westward toward the plains, Schurr said.

He said the Oneota tended to settle in a village on the prairie most of the year to grow crops such as corn, and then retreated to wooded areas for shelter during the winter.

McLeester said researchers are trying to determine how large the Middle Grant Creek site is and whether it was a camp or a village. Either way, evidence suggests it existed for only about 10 years.

The researchers hope to uncover evidence that could point to what ultimately happened to the Oneota people.

They disappeared around the time European pioneers started appearing in the area during the French fur trade era.

Schurr said the Oneota might have assimilated into other historic tribes, but researches don’t know which direction they went.

These and other questions might be answered this summer with the help of volunteers at the site.

“During the dig volunteers will get exposure to all different aspects of archaeological excavation,” McLeester said.

She said volunteers will dig or screen for artifacts after being briefly trained on what to look for.

“Really, we’re looking for anything that’s not dirt,” McLeester said.

She said new volunteers will be paired with a volunteer who has worked at the site previously, such as Gail Pyndus, of LaGrange.

Not only has Pyndus worked at the Middle Grant Creek site but has worked at archaeological sites throughout the country since 2002 through a U.S. Forest Service program called Passport in Time.

“It’s like a treasure hunt,” Pyndus said. “You don’t what you’re going to find, and your first artifact just makes you keep on excavating. It’s fun and exciting. And then there’s the camaraderie of doing it with other people who are just as excited as you are.”

In addition to finding Oneota artifacts researchers also are looking for evidence of the area’s natural environment before Europeans turned the land into farms and pastures.

The Forest Service is trying to convert the more than 20,000 acres of the Midewin National Tallgrass Prairie back into its original prairie habitat, now a rarity here despite Illinois’ Prairie State moniker.

Midewin was converted from part of the old Joliet Arsenal, where ammunition was manufactured for decades. Large bunkers where explosives were stored remain on the site, but are designated for demolition.

For now, one of those bunkers is being used to store the Notre Dame team’s archaeological equipment.

Archeological work starts on July 16 and will run through Aug. 10.

Volunteers must be at least 18 years old and will work about eight hours a day during a four-day session.

Information and applications for volunteers are due by May 14 and can be found online at passportintime.com.